Downloading is what streaming is. If you are asking if they are cached so once they are down, you won’t get that message again as long as you fly in the same area. Then yes, its cached.
Once our street finally got the FTTN to FTTP upgrade I went to Launtel so I went from 24mb to a 1gbit connection. It has been some time since our internet really sucked for many of us. Maybe see if you can get the free fibre upgrade. If you can, there is no reason not to do it.